On iPad I can scroll freely. On desktop with Firefox and Chrome I can't:
I can only go to specific "screen", not in-between them.
Wheel moves with slow transition to the next screen.
I can scroll the wheel super fast and it only does one scroll event at a time, so if I wanted to go quickly from top to bottom with wheel I can't do that. I have to wait for the transition.
I can't middle click (wheel click) to get into free scrolling mode.
There is no scrollbar, only small buttons that I'm supposed to click.
Every convenient way to scroll the page has been disabled on desktop. JavaScript for the sake of JavaScript.
Also, iPad seems broken when I go from vertical to horizontal: suddenly I can only scroll from first screen to the fourth one, and back again.

In typical me fashion, I upgraded right away. Per best practices of most changes per window, I installed the 8.x node release and broke npm
After a reinstall of node and npm, all was well in the world.